Conventionally, portable phones have been demanded to be small in weight, thickness and size, and there has been a request for a technology for reducing the weight, thickness and size of portable phones. On the other hand, there has been a request for an enhanced antenna radiation efficiency. In order to meet these requests, for example, Patent Document 1 discloses a technology relating to a portable phone enhanced in antenna radiation efficiency without spoiling lightness in weight or compactness. In addition, Patent Documents 2 to 4, for example, disclose technologies for enhancing the antenna radiation efficiency of portable phones.    Patent Document 1: Japanese Patent Laid-open No. 2004-153807    Patent Document 2: Japanese Patent Laid-open No. Hei 11-274843    Patent Document 3: Japanese Patent Laid-open No. Hei 7-212835    Patent Document 4: Japanese Patent Laid-open No. 2000-269715
Recently, however, a more higher antenna radiation efficiency has been requested for further reducing the thickness of portable phones. In order to meet this request, it is necessary to develop a dielectric raw material with a further enhanced permittivity. However, an electromagnetic wave shielding body utilizing a dielectric raw material usually tends to be increased in weight when it is tried to enhance its magnetic permeability. Furthermore, recently, there has been an increasing demand for a portable phone with a built-in antenna body, along with the tendency toward a smaller size. In the case of a portable phone equipped with a built-in antenna device, a feeding point and an antenna body are located close to each other. A conventional sheet of magnetic material (electromagnetic wave controlling body), however, would lower the antenna radiation efficiency when disposed in the vicinity of the antenna body; therefore, it has been difficult to apply such a sheet to a built-in antenna device for a portable phone, for example.
Besides, in recent years, an increasing number of ferroconcrete apartment houses and the like have come to be fitted with electric cookers utilizing electromagnetic waves, in place of gas cooking stoves. Attendant on this trend, it is requested to develop an electromagnetic wave shielding body for shielding the human body from the electromagnetic waves generated by such an electric cooker at the time of cooking.